Maintenance - Lennox B050A3B Installation/Servicing Instructions And Users Information Manual

SERVICING THE FURNACE
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD.
Failure to follow safety warnings exactly could result in
dangerous operation, serious injury, death or property
damage.
Improper servicing could result in dangerous operation,
serious injury, death or property damage.
• Before servicing, disconnect all electrical power to
furnace.
• When servicing controls, label all wires prior to
disconnecting. Reconnect wires correctly.
• Verify proper operation after servicing.
The ability to properly perform maintenance on this
equipment requires certain mechanical skills and tools.
If you are at all uncertain, contact your dealer for qualified
maintenance and service since improper service could
lead to furnace shutdown or a hazardous condition which
could lead to an unsafe condition and bodily harm.
Combustion Component Check:
The heat exchanger, gas burners and venting system
must be checked each year, prior to the heating season, by
a qualified dealer/serviceman.
The following procedures should be performed:
1. Remove the burner/manifold assembly from the furnace,
follow the instructions found on this page.
2. Place the burner/manifold assembly on a flat work area
and vacuum the burners. It might be necessary to use a
soft bristly brush to remove dirt and then vacuum.
3. Remove the burner opening inlet plate. This will expose
the burner openings of the primary heat exchangers.
4. Vacuum the length of each heat exchanger tube using a
straight attachment into the burner openings and then
vacuum the burner box.
5. Replace the burner opening inlet plate, and burner/
manifold assembly. Insure that all gaskets are properly
positioned and that no leaks exist.
6. Reattach all wiring and piping as per the wiring diagram
and installation instructions.
7. Turn on utilities and check for leaks using soapy water
and a brush.
506307-01
WARNING
WARNING

MAINTENANCE

8. A visual check of the main burner should be made at the
beginning of each heating season.
9. Check the input rate and adjust if necessary.
10. Perform a safety check of the limit control and pressure
switch.
11. Check the air filter, clean and/or replace as necessary.
12. Replace the appropriate access panels or doors.
Never use an open flame when testing for gas leaks!
Use of an open flame could lead to a fire or explosion!
Many soaps used for leak testing are corrosive to certain
metals. Piping must be rinsed thoroughly with clean water
after leak check has been completed.
Manifold (or Burner/Manifold) Removal/Replacement:
1. Make sure that all utilities (gas and electricity) are turned
off upstream of the furnace.
2. Disconnect the gas line from the gas valve. Be sure that
a wiring diagram is available, or be ready to mark any
wires that are disconnected. Unplug the two (2)
connectors from the gas valve, three (3) connectors from
the rollout switch, flame sensor and sparker ignitor wire.
3. Remove burner access panel and the two (2) screws
holding the forward manifold supports.
4. Slide the burner/manifold assembly forward through the
burner access opening. Being careful not to jare the
sparker or flame sensor.
CONTROL
BOX
COVER
BURNER
ACCESS
PANEL
FORWARD
MANIFOLD
SUPPORT
Issue 1207
WARNING
CAUTION
FURNACE PANEL REMOVAL
BURNER/MANIFOLD
ASSEMBLY
Figure 12
F0000322
BLOWER
ACCESS
PANEL
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